Closure bias



1970 o. BALLANTYNE CLOSURE BIAS Filed July 31, 1969 INVEN'IOR. Davzd 6.Hal la 13 Y ATTORNEY United States Patent 3,541,730 CLOSURE BIAS DavidB. Ballantyne, Southfieltl, Mich., assignor to General MotorsCorporation, Detroit, Mich., a corporation of Delaware Filed July 31,1969, Ser. No. 846,456 Int. Cl. Ef 1/14 U.S. Cl. 49-386 3 ClaimsABSTRACT OF THE DISCLOSURE A bias for selectively and alternatelybiasing a closure member to either closed or open positions with respectto a support member which includes an arcuate semi-rigid channel portionadapted to be secured to one member, a stem portion adapted to besecured to the other member and a pair of arcuately shaped flexible legsextending from a common integral juncture to the stem portion, each legbeing integrally hinged to a respective side of the channel portion. Thelegs are normally biased apart a distance greater than the distancebetween the hinge axes. When the closure member is in closed position,the legs extend inwardly of the channel portion to pull the closuredownwardly and movement of the closure to an open position folds thelegs with respect to each other so that the legs slightly bias the legsof the channel member apart and thereafter move outwardly and unfold tobias the closure member to open position.

This invention relates to a closure bias and more particularly to aclosure bias for interconnecting a swingable closure and its support andselectively and alternately biasing the closure to closed and openpositions with respect to the support.

Conventionally, closures are selectively and alternately biased toclosed and open positions with respect to their supports by varioustypes of over-center spring arrangements. Such arrangements work wellbut have certain disadvantages.

The closure bias of this arrangement works equally as well asconventional arrangements and has the advantages of not requiring anysprings and of being formed of plastic so that it does not requirelubrication and is not subject to deterioration due to ambientconditions.

In the preferred embodiment, the closure bias can be continuouslyextruded of a suitable plastic material, such as polypropylene, andthereafter a section of the continuous extrusion can be cut oil? toprovide a closure bias having the force necessary to bias a particularclosure to its open or closed positions.

Generally, the closure bias includes a semi-rigid channel portion ofarcuate cross section having asymmetrically shaped sides or arms inintegral connecting means for connection to either the closure orsupport. The bias further includes a stem portion having integralconnecting means for connection to the other of either the closure orsupport and a pair of flexible legs which extend oppositely from acommon juncture to the stern portion and have their free ends integrallyhinged to the free ends of the arms of the channel portion. Normally thelegs are integrally biased apart a distance greater than the distancebetween the free ends of the arms. Thus, when the closure is in closedposition, the flexible legs extend inwardly of the channel portion topull the stem inwardly thereof and resist movement of the closure to anopen position. When the closure moves to open position, the legs foldwith respect to each other until the line of engagement of the legsbecomes coplanar or congruent with the hinge axes to slightly bias thearms apart with respect to each other. As

soon as the line of engagement passes out of congruency Patented Nov.24, 1970 with the hinge axes, the arms return to their normal positionand the flexible legs unfold to thereby bias the closure to openposition and, of course, resist movement of the closure from thisposition to its closed position.

One feature of this invention is that the bias includes a pair offlexible legs extending from a common juncture to one member and hingedto the other member for movement on opposite sides of the plane of thehinge axes, with the legs being integrally biased apart a distancegreater than the distance between the hinge axes so as to therebyselectively and alternately bias the one member to the side of the axesfrom which the legs extend. Another feature is that the flexible legsare integrally hinged to spaced arms secured to the other member. Afurther feature is that the flexible legs have a common integraljuncture with the one member and are integrally hinged to spaced armssecured to the other member, with the legs and the common integraljuncture being moved inwardly and outwardly with respect to the arms toselectively and alternately bias the one member to opposite sides of thehinge axes.

These and other features of the invention will be readily apparent fromthe following specification and drawings wherein:

FIG. 1 is a sectional view of a container having a swingable cover, withthe cover and container being interconnected by a closure bias accordingto this invention, with the bias biasing the cover to closed position;

FIG. 2 is a view similar to FIG, 1 showing the bias biasing the cover toopen position;

FIG. 3 is a view similar to FIG. 2 showing the cover in a positionintermediate closed and open positions and the bias in a respectiveposition; and

FIG. 4 is a perspective view of the bias.

Referring now particularly to FIG. 1 of the drawings, a conventionalcontainer or support member 10 includes a cover or closure member 12conventionally hinged thereto at 14 for movement between a closedposition, as shown in FIG. 1, and an open position, as shown in FIG. 2.The cover 12 is alternately biased to its closed position or to its openposition by a closure bias designated generally 16 according to thisinvention. Additionally, the bias 16 resists movement of the closure 12from either terminal position toward the other terminal position.

With reference particularly to FIG. 4, the closure bias 16 includes agenerally arcuately shaped channel portion 18 having an asymmetricalpair of integral semi-rigid arcuately shaped sides or arms 20. Extendingfrom the juncture of the arms 20 is an integral, generally T-shapedportion 22 which, as shown in FIGS. 1 and 2, is adapted to be receivedwithin a shouldered slot or groove 24 in the lower wall of container 10so as to secure the bias 16 thereto. It will be understood, of course,that any other type of suitable attaching means or securement of thechannel portion 18 to the container may likewise be used.

The bias 16 further includes a stem portion 26 having at the free endthereof a generally T-shaped portion 28 which is adapted to be forcedthrough a slot in the cover 12 so as to secure the stem portion 26thereto. Again, as with the portion 22, any other suitable securementmay be used. It will also be understood that the stem portion 26likewise can be secured to the container and the channel portion 18secured to the cover.

A pair of integral arcuate asymmetrical flexible legs 30 extendoppositely'of each other from a common integral juncture 32 to the sternportion 26. The free end of each leg 30 is integrally hinged at 34 tothe free end of a respective arm 20 of the channel portion 18.

It is intended that the closure bias 16 be formed by any suitablemethod, such as by continuous extrusion, or by molding. If formed byextrusion, whatever section of bias is necessary for a particularclosure and support, will be cut from the extrusion. While any suitableplastic material can be used, preferably the bias 16 is formed ofpolypropylene.

With particular regard to FIG. 4, normally the legs 30 have an integralbias tending to force the free ends of the legs apart with respect toeach other a distance which is greater than the distance between theaxes of hinges 34. Thus, when the legs 30 extend inwardly of the arms 20of channel portion 18, this integral bias of the legs 30 acting againstthe arms 20 through hinges 34 tends to pull or bias the common integraljuncture 32 inwardly of the channel portion 18. This in turn moves thestem portion 26 inwardly of the channel portion to bias the cover 12 toits closed position, as shown in FIG. 1, and to likewise resist movementof the cover toward its open position.

When the cover is moved from its closed position of FIG. 1 toward itsopen position of FIG. 2, the flexible legs 30 told with respect to eachother or move into engagement with each other from their common integraljuncture 32 as the stem portion 26 and the common integral juncture moveoutwardly from between the arms 20 of the channel portion 18. When theline of engagement of the engaged portions of the legs moves intocongruency with the hinge axes 34 or becomes coplanar therewith, asshown in FIG. 3, the bias is in a theoretical equilibrium positionwherein it does not bias the closure 12 to either position. In thisposition, it will be noted that the legs 30 have slightly forced thearms 20 apart with respect to each other from their normal position,shown in FIGS. 1, 2 and 4. Thereafter upon any slight movement'of theline of engagement out of congruency with the hinge axes 34, the bias ofthe legs 30 and the bias of the arms 20 immediately apply a bias to thecover 12 biasing the cover to its open position, as shown in FIG. 2, andof course resisting any movement of the cover 12 toward closed position.The position of the bias shown in FIG. 3 is ordinarily not a stableposition since it is ditficult to maintain the line of engagement oflegs 30 congruent or coplanar with the axes of hinges 34. Although thebias 16 has been shown with the legs 30 integral with the stem portion26, these legs could likewise be formed in a separated condition andthereafter joined to each other to form the stem portion. Likewise,although these legs are shown integrally hinged to the arms 20, theycould be hinged to the arms 20 in the conventional manners without beingintegral therewith.

Thus this invention provides an improved I claim:

1. In combination with a closure member swingably mounted on a supportmember, a closure bias for selectively and alternately biasing theclosure member to closed closure bias.

and open positions comprising, in combination, means secured to onemember and providing a pair of spacedhinge axes, a pair of flexible legsextending oppositely of each other from a common juncture to the othermember and being integrally biased apart a distance greater than thetransverse distance between the hinge axes, eachleg being hinged about arespective one of the axes, the legs being movable between an unfoldedposition with respect to each other wherein the legs extend in onedirection from the hinge axes to bias the common juncture in the onedirection and bias the closure member to oneposition thereof, and afolded position with respect to each other wherein the legs extend in anopposite direction from the hinge axes to bias the common juncture inthe opposite direction and bias the closure member to the other positionthereof, the portions of the legs adjacent the common juncture movinginto engagement with each other as the legs move in the oppositedirection until the L1 engaged portions of the legs move outwardly ofthe plane of the hinge axes, the engaged portions of the legs thereaftermoving out of engagement with each other.

2. In combination with a closure member swingably mounted on a supportmember, a bias for selectively and alternately biasing the closuremember to closed and open positions comprising, in combination, a pairof spaced arms secured to one member, a pair of flexible legs extendingoppositely of each other from a common juncture to the other member andbeing integrally biased apart a distance greater than the distancebetween the arms, each leg being integrally hinged to a respective oneof the arms, the legs being movable between an unfolded position withrespect to each other wherein the legs extend inwardly of the arms fromthe integral hinges to bias the common juncture inwardly of the arms andbias the closure member to one position thereof, and a folded positionwith respect to each other wherein the legs extend outwardly of the armsfrom the integral hinges to bias the common juncture outwardly of thearms and bias the closure member to the other position thereof, theportions of the legs adjacent the common juncture thereof moving intoengagement with each other as the legs move outwardly of the arms untilthe line of engagement of the engaged portions becomes congruent withthe integral hinge axes, the engaged portions of the legs thereaftermoving out of engagement with each other as the line of engagement movesout of congruency with the integral hinge axes.

3. In combination with a closure member swingably mounted on a supportmember, an integral bias for selectively and alternately biasing theclosure member to closed and open positions comprising, in combination,a pair of integral spaced semi-rigid arms secured to one member, a pairof flexible legs extending oppositely of each other from a commonintegral juncture to the other member and being integrally biased aparta distance greater than the distance between the arms, each leg beingintegrally hinged to a respective one of the arms, the legs beingmovable between an unfolded position with respect to each other whereinthe legs extend inwardly of the arms from the integral hinges, the biasof the legs being resisted by the arms whereby the legs bias the commonintegral juncture inwardly of the arms to bias the closure member to oneposition thereof, and a folded position with respect to each otherwherein the legs extend outwardly of the arms from the integral hinges,the bias of the legs being resisted by the arms whereby the legs biasthe common integral juncture outwardly of the arms to bias the closuremember to the other position thereof, the portions of the legs adjacentthe common integral juncture thereof moving into engagement with eachother as the legs move outwardly of the arms to move the arms apart withrespect to each other whereby the arms resist until the engaged portionsof the legs move outwardly of the integral hinges, the engaged portionsof the legs thereafter moving out of engagement with each other as thearms return to their normal position.

References Cited UNITED STATES PATENTS 2,514,033 7/1950 Dean 16-732,850,200 9/1958 Hofmann. 2,985,335 5/1961 Slater. 3,287,757 11/1966 VanNoord l672 KENNETH DOWNEY, Primary Examiner US. (:1. X.R. l6-72; 220 31,35

